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Article
Publication date: 22 November 2017

Gerda Mikalauskaite and Virginija Daukantiene

The purpose of this paper is to determine the influence of the loading velocity on textile bonds and sewn seam strength.

Abstract

Purpose

The purpose of this paper is to determine the influence of the loading velocity on textile bonds and sewn seam strength.

Design/methodology/approach

Commercially produced polyamide and polyester knitted fabric, and polyester woven fabrics as well as three commercially available monolayer urethane thermoplastic films were used in this research. Two layers of each fabric were laminated at 160°C temperature at 5.6 kPa for 20 seconds. Sewn specimens were joined applying (301) and (514) stiches for woven and knitted fabrics, respectively. The bond and sewn seam strength was investigated at different delamination loading velocities (50, 100, 150, 200, 300 mm/min). These values of velocities lies in the velocity interval which covers the different standard requirements for testing of the quality of textiles and their seams or were applied in the research works of previous scientists. As the influence of loading velocity was more significant for bond strength, the bond strength results were analyzed together with the analysis of bond rupture character.

Findings

The determined influence of the loading velocity on textile bonds strength has proved that the loading velocity in bond strength test is of high importance for the prediction of the behavior of clothing being in exploitation under different conditions. The opposite tendency was determined for the sewn seams, the strength of which was independent on loading velocity.

Originality/value

The influence of the loading velocity on textile bond and sewn seam strength was not analyzed in the previous research works published by other scientists. It was known that the standard velocity is 50 mm/min for seams and 100 mm/min for textiles strength testing. It was shown there that the real exploitation of a garment as a whole complicated heterogenic dynamic system could be simulated with changing loading velocities during their seam strength testing. It was also determined that the loading velocity makes different influence on bonded and sewn seams of textiles.

Details

International Journal of Clothing Science and Technology, vol. 29 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 February 1987

R.L. Shook

A study was undertaken to evaluate the thermosonic gold‐wire bonding capability to Ti‐Pd‐Cu‐Ni‐Au thin film metallisation on newly developed polymer hybrid integrated circuits…

Abstract

A study was undertaken to evaluate the thermosonic gold‐wire bonding capability to Ti‐Pd‐Cu‐Ni‐Au thin film metallisation on newly developed polymer hybrid integrated circuits (POLYHICs). (The POLYHIC technology incorporates alternating layers of polymer and metal added to conventional Hybrid Integrated Circuits which provide for increased interconnection density.) Destructive wire‐pull strengths were measured as a function of varying wire‐bonding machine operating parameters of wedge bond force, wedge bond time, temperature, and ultrasonic energy. All data were evaluated and compared with wire bonding under similar conditions to thin film circuits on Al2O3 ceramic. The results for wedge‐bond associated failures indicated that machine operating parameters of wedge bond force, time and ultrasonic energy similarly affected the average wire‐pull strength for both the ceramic and POLYHIC circuits. Pull strengths for equivalent metallisation schemes and bonding parameters were generally slightly higher and more tightly distributed for bonds made to metal films on ceramic. A strong correlation was found to exist between wire‐pull strengths and surface topography (as measured by a profilometer technique) of the thin film metallisation for the POLYHICs which had both smooth and rough metallisation surfaces for metal films on top of the polymer. The results indicated that rough metallisation bonded more easily and yielded much higher wire‐pull strengths. Also, rougher films were shown to effectively increase the parameter‐operating windows for producing reliable wire bonds. A semi‐quantitative analysis was developed to help explain this correlation. Surface topography effects were also found to be a key factor when evaluating wire bondability as a function of substrate bonding temperature. Wedge‐bond strength was essentially independent of temperature for bonds made to rougher metallisation while a strong temperature dependency was found when wire bonds were made to smoother films.

Details

Microelectronics International, vol. 4 no. 2
Type: Research Article
ISSN: 1356-5362

Article
Publication date: 20 March 2017

Timothy J. Coogan and David Owen Kazmer

The purpose of this paper is to investigate the factors governing bond strength in fused deposition modeling (FDM) compared to strength in the fiber direction.

1771

Abstract

Purpose

The purpose of this paper is to investigate the factors governing bond strength in fused deposition modeling (FDM) compared to strength in the fiber direction.

Design/methodology/approach

Acrylonitrile butadiene styrene (ABS) boxes with the thickness of a single fiber were made at different platform and nozzle temperatures, print speeds, fiber widths and layer heights to produce multiple specimens for measuring the strength.

Findings

Specimens produced with the fibers oriented in the tensile direction had 95 per cent of the strength of the constitutive filament. Bond strengths ranged from 40 to 85 per cent of the filament strength dependent on the FDM processing conditions. Diffusion, wetting and intimate contact all separately affect bond strength.

Practical implications

This study provides processing recommendations for producing the strongest FDM parts. The needs for higher nozzle temperatures and more robust feed motors are described; these recommendations can be useful for companies producing FDM products as well as companies designing FDM printers.

Originality/value

This is the first study that discusses wetting and intimate contact separately in FDM, and the results suggest that a fundamental, non-empirical model for predicting FDM bond strength can be developed based on healing models. Additionally, the role of equilibration time at the start of extrusion as well as a motor torque limitation while trying to print at high speeds are described.

Details

Rapid Prototyping Journal, vol. 23 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 8 September 2021

Renjini Girija and Sudhakar Rajagopal

Bond strength is an indicator of the quality of the fusing process. The study's primary purpose is to predict the bond strength using easily measurable variables. This study…

Abstract

Purpose

Bond strength is an indicator of the quality of the fusing process. The study's primary purpose is to predict the bond strength using easily measurable variables. This study focuses on shirting fabrics fused with woven interlinings and changes in bond strength before and after washing.

Design/methodology/approach

This study attempts to model and predict bond strength of fused shirt composites using an initial screening design followed by full factorial design of experiments. After screening out, those found significantly affecting the bond strength are fabric fiber content, interlining areal weight and fusing temperature. This study proposes the regression models explaining the effect of the three variables on bond strength before and after washing the fused composites.

Findings

This study found that heavy interlinings (250 g/sq.m) require higher fusing temperatures than the lighter interlining (225 g/sq.m). After washing, the bond strength of samples fused at high temperatures reduced in some instances. Maintaining a high temperature without considering interlining weight can lower the bond strength after washing the fused composites.

Originality/value

A combination of screening and full factorial DOE is used to analyze and predict bond strength of composites comprising medium-weight shirting fabrics and heavier weight interlinings used in shirts.

Details

Research Journal of Textile and Apparel, vol. 26 no. 4
Type: Research Article
ISSN: 1560-6074

Keywords

Article
Publication date: 4 June 2021

Niragi Dave, Ramesh Guduru, Anil Kumar Misra and Anil Kumar Sharma

The consumption of supplementary cementitious materials (SCMs) has increased enormously in the construction industry. These SCMs are often waste materials or industrial…

Abstract

Purpose

The consumption of supplementary cementitious materials (SCMs) has increased enormously in the construction industry. These SCMs are often waste materials or industrial by-products. This study aims to investigate the bond strength using reinforcing bars in Normal Strength Concrete (M20 grade) and High Strength Concrete (M40 grade), developed using SCMs and data was compared with concrete prepared with ordinary portland cement (OPC). The findings of the study will help in reducing the dependency on OPC and promote the utilization of waste materials in Construction.

Design/methodology/approach

In the present study, the bond behavior between the steel bars and the concrete was investigated in controlled, binary and quaternary concretes of M20 and M40 grades. Following the conventional procedures, samples were prepared and mechanical tests conducted (as per IS:2770–1 code for M20 and M40 grade concrete structures), which showed an improvement in the bond strength depending on the extent of overall calcium and silica content in these composite mixtures, and thus reflected the importance of vigilant utilization of used industrial waste in the OPC as a replacement without exceeding silica content beyond certain percentages for enhanced structural properties.

Findings

Experimental evaluation of bond behavior results showed a brittle nature for the controlled (OPC) concrete mixtures. While binary and quaternary concrete was able to resist the load-carrying capacity under large deformations and prevented the split cracking and disintegration of the concretes. Among different variations in the chemistry, for both M20 and M40 grades, the maximum bond strengths were observed for 10% Metakaolin + 10% Silica Fume + 30% Fly Ash + 50% OPC composition and this could be attributed to the fineness of the additives, better packing and enhanced calcium silicate hydrate (C-S-H).

Originality/value

Quaternary concrete may be a future option in place of OPC concrete. Very limited data is available related to the bond strength of quaternary concrete. Experimental analysis on quaternary concrete shows that its use in construction can reduce both construction cost and a burden on natural raw materials used to make OPC.

Details

Journal of Engineering, Design and Technology , vol. 20 no. 6
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 18 April 2017

Timothy J. Coogan and David O. Kazmer

The purpose of this paper is to present a diffusion-controlled healing model for predicting fused deposition modeling (FDM) bond strength between layers (z-axis strength).

1414

Abstract

Purpose

The purpose of this paper is to present a diffusion-controlled healing model for predicting fused deposition modeling (FDM) bond strength between layers (z-axis strength).

Design/methodology/approach

Diffusion across layers of an FDM part was predicted based on a one-dimensional transient heat analysis of the interlayer interface using a temperature-dependent diffusion model determined from rheological data. Integrating the diffusion coefficient across the temperature history with respect to time provided the total diffusion used to predict the bond strength, which was compared to the measured bond strength of hollow acrylonitrile butadiene styr (ABS) boxes printed at various processing conditions.

Findings

The simulated bond strengths predicted the measured bond strengths with a coefficient of determination of 0.795. The total diffusion between FDM layers was shown to be a strong determinant of bond strength and can be similarly applied for other materials.

Research limitations/implications

Results and analysis from this paper should be used to accurately model and predict bond strength. Such models are useful for FDM part design and process control.

Originality/value

This paper is the first work that has predicted the amount of polymer diffusion that occurs across FDM layers during the printing process, using only rheological material properties and processing parameters.

Details

Rapid Prototyping Journal, vol. 23 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 14 October 2021

Hala Mohamed Elkady, Ola Bakr Shalaby, Mohamed Kohail and Elsayed Abdel Raouf Nasr

This paper presents the second part of the investigation on resistance to elevated temperatures of a proposed hybrid composite concrete (NCSF-Crete) mix. The composite including…

Abstract

Purpose

This paper presents the second part of the investigation on resistance to elevated temperatures of a proposed hybrid composite concrete (NCSF-Crete) mix. The composite including nano metakaolin (NC) and steel fibers (SF) in addition to regular concrete components has proven -in the first published part-earlier promoted fresh concrete behavior, and to have reduced loss in compressive strength after exposure to a wide range of elevated temperatures. This presented work evaluates another two critical mechanical characteristics for the proposed composite -namely- splitting and bond strengths.

Design/methodology/approach

A modified formula correlating splitting and compressive strength (28 days) based on experiments results for NCSF is proposed and compared to formulas derived for regular concrete in different design codes. Finally, both spitting and bond strengths are evaluated pre- and post-exposure to elevated temperatures reaching 600 °C for two hours.

Findings

The proposed NCSF-Crete shows remarkable fire endurance, especially in promoting bond strength as after 600 °C heat exposure tests, it maintained strength equivalent to 70% of a regular concrete control mix at room temperature. Improving residual splitting strength was very significant up to 450 °C exposure.

Research limitations/implications

Obvious deterioration is monitored in splitting resistance for all concretes at 600 °C.

Practical implications

This proposed composite improved elevated heats resistance of the most significant concrete mechanical properties.

Social implications

Using a more green and sustainable constituents in the composite.

Originality/value

The proposed composite gathers the merits of using NC and SF, each has been investigated separately as an addition to concrete mixes.

Details

Journal of Structural Fire Engineering, vol. 13 no. 1
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 2 January 2018

Hongbin Li, Taiyong Wang, Jian Sun and Zhiqiang Yu

The purpose of this paper is to study the effects of these major parameters, including layer thickness, deposition velocity and infill rate, on product’s mechanical properties and…

1399

Abstract

Purpose

The purpose of this paper is to study the effects of these major parameters, including layer thickness, deposition velocity and infill rate, on product’s mechanical properties and explore the quantitative relationship between these key parameters and tensile strength of the part.

Design/methodology/approach

A VHX-1000 super-high magnification lens zoom three-dimensional (3D) microscope is utilized to observe the bonding degree between filaments. A temperature sensor is embedded into the platform to collect the temperature of the specimen under different parameters and the bilinear elastic-softening cohesive zone model is used to analyze the maximum stress that the part can withstand under different interface bonding states.

Findings

The tensile strength is closely related to interface bonding state, which is determined by heat transition. The experimental results indicate that layer thickness plays the predominant role in affecting bonding strength, followed by deposition velocity and the effect of infill rate is the weakest. The numerical analysis results of the tensile strength predict models show a good coincidence with experimental data under the elastic and elastic-softened interface states, which demonstrates that the tensile strength model can predict the tensile strength exactly and also reveals the work mechanism of these parameters on tensile strength quantitatively.

Originality/value

The paper establishes the quantitative relationship between main parameters including layer thickness, infill rate and deposition velocity and tensile strength for the first time. The numerically analyzed results of the tensile strength predict model show a good agreement with the experimental result, which demonstrates the effectiveness of this predict model. It also reveals the work mechanism of the parameters on tensile strength quantitatively for the first time.

Details

Rapid Prototyping Journal, vol. 24 no. 1
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 3 October 2016

Nur Khaida Baharuddin, Fadzli Mohamed Nazri, Ramadhansyah Putra Jaya and Badorul Hisyam Abu Bakar

This study aims to investigate and compare the interfacial bond characteristics between fire-damaged normal concrete substrate and ultra-high-performance fiber-reinforced concrete…

Abstract

Purpose

This study aims to investigate and compare the interfacial bond characteristics between fire-damaged normal concrete substrate and ultra-high-performance fiber-reinforced concrete (UHPFRC) as a repair material.

Design/methodology/approach

First, fire-damaged normal concrete was prepared. Then, with a cast surface, the substrate was subjected to different surface moisture conditions. Three types of moisture conditions were set, namely, air dry, saturated surface dry (SSD) and wet. Slant shear and splitting cylinder tests were conducted to determine the interfacial bond strength of the composite.

Findings

In general, results indicate that surface moisture conditions significantly influence bond strength. The substrate under SSD condition exhibited the highest bond strength. The findings suggest that UHPFRC is a promising material for the repair and reuse of fire-damaged concrete structures.

Originality/value

This study compares the bond strength between fire-damaged normal concrete and UHPRC.

Details

World Journal of Engineering, vol. 13 no. 5
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 25 January 2021

Ying-Ji Chuang and Hsing-Chih Tsai

This paper aims to use a derivative of genetic programming to predict the bond strength of glass fiber-reinforced polymer (GFRP) bars in concrete under the effects of design…

Abstract

Purpose

This paper aims to use a derivative of genetic programming to predict the bond strength of glass fiber-reinforced polymer (GFRP) bars in concrete under the effects of design guidelines. In developing bond strength prediction models, this paper prioritized simplicity and meaningfulness over extreme accuracy.

Design/methodology/approach

Assessing the bond strength of GFRP bars in concrete is a critical issue in designing and building reinforced concrete structures.

Findings

Ultimately, the equation of a linear form of a particular design guideline was suggested as the optimal prediction model. Improvements to the current design guidelines suggested by this model include setting a 1.31 magnification and considering the effects of the three significant parameters of bar diameter (db), minimum cover-to-bar diameter (C/db) and development length to bar diameter (l/db) under an acceptable root mean square error accuracy of around 2 MPa. Furthermore, the model suggests that the original influence parameter of concrete compressive strength (fc) may be removed from bond strength calculations.

Originality/value

The model suggests that the original influence parameter of concrete compressive strength (fc) may be removed from bond strength calculations.

Details

Engineering Computations, vol. 38 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

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